/Engine/Plugins/Experimental/FullBodyIK/Source/FullBodyIK/Public/JacobianSolver.h
Bydefault, we use JPIDLS, but it is cheaper to use Jacobian Transpose at the cost of solver
class FJacobianSolverBase
FCalculateParti...
OnCalculatePartialDerivativesDelegate
FCalculateTarge...
OnCalculateTargetVectorDelegate
FPostProcessDel...
OnPostProcessDelegateForIteration